An ambitious young executive is sent to retrieve his company’s CEO from an idyllic but mysterious “wellness center” at a remote location in the Swiss Alps but soon suspects that the spa’s miraculous treatments are not what they seem.

It sounded like just another urban legend: A videotape filled with nightmarish images, leading to a phone call foretelling the viewer’s death in exactly seven days. As a newspaper reporter, Rachel Keller was naturally skeptical of the story, until fo…